Semiconducting Sn3O4 nanobelts: Growth and electronic structure

Abstract

The study of structures based on nonstoichiometric SnO 2−x compounds, besides experimentally observed, is a challenging task taking into account their instabilities. In this paper, we report on single crystal Sn 3 O 4 nanobelts, which were successfully grown by a carbothermal evaporation process of SnO 2 powder in association with the well known vapor-solid mechanism. By combining the structural data and transport properties, the samples were investigated. The results showed a triclinic semiconductor structure with a fundamental gap of 2.9 eV. The semiconductor behavior was confirmed by the electron transport data, which pointed to the variable range hopping process as the main conduction mechanism, thus giving consistent support to the mechanisms underlying the observed semiconducting character.

Sn3O4 single crystal nanobelts grown by carbothermal reduction process

“…Raman spectroscopy evidenced that Sn 3 O 4 is a very crystalline material with a low amount of defects as can be seen by two sharp, symmetric and strong peaks at 145 and 172 cm À 1 (Fig. 1d), which are the main phonon modes detected in Sn 3 O 4 triclinic structure [10]. As observed in XRD, SnO and SnO 2 vibrational modes were also identified with weak intensity in the Raman spectra, indicated as triangle and star, respectively.…”

“…Here g(E F ) is the density of states at the Fermi level, a À 1 the localization length, b¼5.7 and m¼1/4 for the VRH process in three dimensions [24]. In this model the localized electrons can contribute to the conduction if they experience inelastic scattering process, which causes the electrons to hop from one site to another since they have similar energy [10,25]. For this purpose phonons are required to conserve the energy during the hops; the higher the phonon density the bigger the carrier mobility through localized states that cause the hopping events to grow.…”

“…As proposed by theoretical calculations [5][6][7], the Sn 3 O 4 structure presents an energy gap that was experimentally confirmed [10] in the visible portion of the electromagnetic spectrum, which is very attractive from the point of view optical applications. Besides this tin oxide has been widely used as a gas sensor, as Sn 3 O 4 is composed of two different oxidation states, which can provide selectivity properties in sensor devices.…”

The nature of paramagnetic defects in tin (IV) oxide

“…The lattice parameters were found to be consistent with a monoclinic cell which is a distorted superlattice of the cassiterite structure. Berengue et al studied single crystal Sn 3 O 4 nanobelts, which were grown by a carbothermal evaporation process from SnO 2 powder [48]. Obtained structural data provide experimental evidences of a layered growth: the whole structure can be seen as alternated SnO 2 -like and SnO-like layers.…”

Spray deposited Mg-doped SnO2 thin film LPG sensor: XPS and EDX analysis in relation to deposition temperature and doping

“…2 [22]. Fingerprints for the formation of suboxides on smaller scale in films deposited above a temperature of 355 °C are observed [23], but these are beyond scope of this report. [24,25] suggest that the surface energy sequence of SnO 2 is Є(110) < Є(100) < Є(101) < Є(001).…”